[cayossarian]

Consolidates the [2.1.2] CHANGELOG section into user-facing, grouped entries, described against 2.1.1.

• r202639 details (battery meter sign, a circuit for every inverter, SPAN Drive charge-current limits, registration that asks setup to wait) fold into the r202639 support entry.
• Related fixes are grouped: device-lookup deprecations, credential rotation, GFE Override and DSM Grid State, energy dip compensation, withdrawn circuit controls, and card fixes.
• Behaviour users already assume is no longer listed.

CHANGELOG only; no code changes. The v2.1.2b7 release notes already carry the same section.